1. Field of the Invention
This invention relates to a closure system including a container and a cap, the closure system having interengaged locking members which not only prevent unscrewing of the cap on the container neck when the cap is fully screwed on the neck but which also position the cap relative to the container in a predetermined position. The invention also includes a tamper evident tear out section which will give a visual indication of an attempt to unscrew the cap from the container.
2. Background Information
It is well known to provide closures for containers. One type of commonly used closure consists of a cap having a dispensing opening and a hinged lid. The cap is typically provided with internal threads which engage external threads on the container neck to allow the closure to be screwed onto the container. In use, the hinged lid is pivoted away from the cap to expose the dispensing opening, thus allowing the contents of the container to be dispensed.
It is also well known to provide closures having tamper evident means which provide a visual and mechanical indication that the container has been opened or tampered with. Some of these closures are provided with tamper evident means which are actuated by attempting to unscrew the cap from the container. See, e.g., U.S. Pat. Nos. 2,414,420; 4,197,955; and 4,372,456.
U.S. Pat. No. 4,534,477 discloses a childproof of bottle. The bottle and cap are provided with a gap near the lower end of the thread in the cap and a projection on the outer surface of the container neck. A "flag" springs outward into a gap in the threaded cap when an attempt is made to unscrew the cap. The flag is torn off by continued unscrewing of the cap. This provides a visual indication of tampering with the container.
U.S. Pat. No. 4,289,248 provides a container closure assembly having intermediate positioning means. The closure assembly has detent means for positive positioning of the closure with respect to the container at a preselected intermediate position between full closure-container cooperation and non-cooperative relationship.
Despite these devices, there remains a need for a closure system that locks the cap onto the container neck and which provides a visual indication of any attempt to unscrew the cap from the container. Also, there remains a need for a closure system associated with a non-cylindrical cap and a non-cylindrical container which has locking members that position the dispensing opening relative to the container in a predetermined position.